초록 ▼

A method and apparatus for controlling the surge limit of a turbocompressor utilizes continuously measured pressure and temperature values at the suction and outlet sides of the compressor. A relief valve connected to the outlet side of the compressor is controlled as a function of the distance betw

A method and apparatus for controlling the surge limit of a turbocompressor utilizes continuously measured pressure and temperature values at the suction and outlet sides of the compressor. A relief valve connected to the outlet side of the compressor is controlled as a function of the distance between a working point and a surge limit line or blow-off line of a characteristic graph produced by characteristic graph coordinates that are computed using the pressure and temperature values. The actual value of another operating parameter that is independent of the pressure and the temperature values, such as the speed of the turbine for the turbocompressor, for example, is used. This operating parameter defines a family of characteristic lines on the characteristic graph. A set-point value for the characteristic graph coordinates is then obtained using the characteristic line of the operating parameter which passes through the working point. If the set point value thus found does not correspond to the actual value for the operating parameter, a control signal is generated which can either be used to influence the relief valve or for generating a warning signal.

대표청구항 ▼

A method of controlling a gas conveying turbocompressor having a suction side, an outlet side and a relief valve connected to the outlet side which can be opened and closed as a function of the distance between a working point and at least one of a surge limit line and a blow-off line which are plot

A method of controlling a gas conveying turbocompressor having a suction side, an outlet side and a relief valve connected to the outlet side which can be opened and closed as a function of the distance between a working point and at least one of a surge limit line and a blow-off line which are plotted on a characteristic graph, the turbocompressor operating at a momentary working point lying at a point in the characteristic graph, the blow-off line and surge limit line of the characteristic graph being plotted using predetermined theoretical coordinates which are a function of theoretical flow parameters including suction gas temperature, suction gas pressure, volumetric flow rate, outlet gas pressure and gas composition at the suction and outlet sides of the compressor, the method comprising: continuously measuring the suction gas pressure and suction gas temperature at the suction side and outlet gas pressure at the outlet side of the compressor; calculating the actual characteristic graph coordinates at the gas composition using the continuously measured pressures and tempertures representing a momentary working point of the turbocompressor; continuously measuring the actual value of the speed of the compressor, which is used to define a family of characteristic lines on the characteristic graph; obtaining a set point value for the speed on the characteristic graph using a characteristic line generated by the speed which passed through the momentary working point of the compressor as it appears on the characteristic graph; comparing the actual value of the speed to the set point value therefor; and generating a correction signal indicating a change in gas composition if the actual value of the monitoring parameter deviates from the set point value therefor.